U.S. [f. UNI- 2 + CYCLE, after bicycle, tricycle.] A vehicle or conveyance having only one wheel; esp. a monocycle used by acrobats or for gymnastic displays.

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1869.  The Velocipede (N.Y.), April, 76. Hemmings’ Unicycle or ‘Flying Yankee Velocipede.’

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1884.  Knight, Dict. Mech., Suppl. 913/1. Unicycle, a one-wheeled vehicle for propulsion by foot-power.

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  Hence Unicyclist, one who rides a unicycle.

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1881.  Sells Bros. Show-Bill. Celebrated Russian Bicyclists, Unicyclists, and Roller Skaters.

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